On Mon, Jan 06, 2003 at 12:01:41PM +0530, Rupa wrote: > > Actually this was the question asked in some exam. I do no how to calculate > size of page table. They had given 4 answers... > i)16mb ii)8mb > iii)2mb iv) 24mb As I see it, there are some data missing - how many levels does the page-table have and how big is the page-table entry. Let's assume it's i386. Then each pte is 4 bytes + 1 directory. That is 4bytes for each 4kB of virtual memory, that is 1/1000 of the virtual address space. Virtual address space is 4GB. That makes 4MB + 4kB for the directory. Actual size will however be much smaller, because only non-empty page-table pages will be allocated. That does not look like a good answer for you :-(. > You have any idea? > > Regards, > Rupa > ----- Original Message ----- > From: "Raghu R. Arur" <rra2002@cs.columbia.edu> > To: "Rupa" <rupa.ramakrishna@ionidea.com> > Sent: Monday, January 06, 2003 11:47 AM > Subject: Re: size of page table > > > > > > Hi, > > > > If you are talking about linux, the page table size is not related to the > > memory size (RAM size). page table is for per process and in linux each > > process will have 4GB of memory allocated. 3 GB for the user space and 1 > > GB for the kernel space. > > > > HTH, > > raghu > > > > On Mon, 6 Jan 2003, Rupa wrote: > > > > > Hello, > > > I have small doubt regarding the sizeof page table. Consider a > machine with 64MB physical memory and a 32 bit virtual address space. If the > page size is 4kb, what is the approximate size of page table.? > > > Any help will be useful > > > > > > Rupa > > > > > > > -- > Kernelnewbies: Help each other learn about the Linux kernel. > Archive: http://mail.nl.linux.org/kernelnewbies/ > FAQ: http://kernelnewbies.org/faq/ > ------------------------------------------------------------------------------- Jan 'Bulb' Hudec <bulb@ucw.cz> -- Kernelnewbies: Help each other learn about the Linux kernel. Archive: http://mail.nl.linux.org/kernelnewbies/ FAQ: http://kernelnewbies.org/faq/
